OpenVPN server in Linux Containers

This article describes how to setup a Linux Container to run OpenVPN in server mode for secure/private internet use. Doing so offers a distinct advantage over using full-blown virtualization like VirtualBox or QEMU in that the resource overhead is minimal by comparison and able to run on low powered devices.

Needed packages within the container

In addition to the base system, openvpn is required and available from the official repositories. A properly configured firewall to run within the container is highly recommended. This guide uses ufw which is very easy to configure, but other examples can certainly be used.

Package setup

OpenVPN

Refer to the OpenVPN article to properly setup the home server. Verify openvpn functionality within the container; start openvpn via openvpn@myprofile.service and once satisfied enable it to run at boot.

Note: Users running openvpn within an unprivileged container will need to create a custom systemd unit to start it within the container. Simply copy the package-provided /usr/lib/systemd/system/openvpn-server@.service to /etc/systemd/system/openvpn-server@.service and modify the new file commenting out the the line beginning with: LimitNPROC...

ufw

Refer to OpenVPN#Firewall configuration to setup the routes and firewall within the container. Failure to do so or to implement with an alternative will prevent openvpn from functioning properly in the container.